Unable to edit hosted feature layers in ArcGIS Enterprise

Description

In ArcGIS Enterprise, features in hosted feature layers cannot be created or edited. This issue affects editing workflows across multiple platforms, including Map Viewer, ArcGIS Field Maps, and other apps. When it occurs, the ArcGIS Server Manager log file records an error message similar to the following example.

Error:
0 : ERROR: cannot execute <query> in a read-only transaction  
Where: SQL statement "SELECT base_id, num_ids FROM <target_table> WHERE id_type = 2 ORDER BY num_ids DESC FOR UPDATE"  
PL/pgSQL function <id_generation_function>(integer, integer) line 45 at OPEN  
SQL statement "SELECT sql_code, o_base_id, o_num_obtained_ids FROM <id_generation_function>(2, 1)"  
PL/pgSQL function <rowid_management_function>(character varying, character varying) line 34 at EXECUTE

Cause

The issue occurs when ArcGIS Data Store (relational) silently switches to read-only mode, preventing any operation that writes to the hosted layer. This is because the ArcGIS Data Store has a built-in safeguard mechanism that automatically changes the data store mode to read-only when the disk space on the machine hosting the relational data store drops below a critical threshold.

Solution or Workaround

1. Increase the disk space of the ArcGIS Data Store machine. Refer to ArcGIS Enterprise: Disk space requirements for more information.
2. Change the relational data store from read-only to read-write mode. Refer to the solution section of the following article, Error: Failed to submit ArcGIS Survey123 response. Database error has occurred for instructions.